Forehead pad for respiratory mask

ABSTRACT

A forehead pad for use in a respiratory mask with a forehead support, which includes a base portion to contact a user&#39;s forehead, a support post connected to the base portion, and a head adapted to connect the support post to a forehead support. A pair of forehead pads may be joined with a connector.

CROSS-REFERENCE TO PRIORITY APPLICATIONS

[0001] The present application claims the benefit of U.S. ProvisionalApplication Serial No. 60/424,696 filed Nov. 8, 2002 and U.S.Provisional Application Serial No. 60/467,572 filed May 5, 2003, and thepresent application is a Continuation-In-Part of U.S. Non-ProvisionalApplication Serial No. 10/235,846 filed Sep. 6, 2002, which in turnclaims priority to U.S. Provisional Patent Application Serial No.60/317,486 filed Sep. 7, 2001 and U.S. Provisional Patent ApplicationSerial No. 60/342,854 filed Dec. 28, 2001. Each of the aboveapplications is hereby incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The invention relates to forehead pads. These pads can be usedwith a respiratory mask for Non-invasive Positive Pressure Ventilation(NPPV) treatment of Sleep Disordered Breathing (SDB).

[0004] 2. Background of the Invention

[0005] Nasal masks are commonly used in the treatment of respiratoryconditions and sleep disorders by delivering a flow of breathable gas toa user to either assist the user in respiration or to provide atherapeutic form of gas to the user to prevent sleep disorders such asobstructive sleep apnea (OSA). These nasal masks typically receive a gasthrough a supply line, which delivers the gas into a chamber formed bywalls of the mask.

[0006] The mask is generally semi-rigid and has a face portion that isin communication with the nose and/or mouth of a user. The mask isnormally secured to the user's head by straps. The straps are adjustedto pull the mask against the face with sufficient force to achieve agas-tight seal between the mask and the user's face. Gas is thusdelivered to the mask through the aperture to the user's nasal passagesand/or mouth.

[0007] One of the problems that arises with the use of the mask is thatin order for the straps to be tight, the mask is compressed against theuser's face and may push unduly hard on the user's nose. Additionallythe mask may move around on the user's face. Therefore, masks oftencontain a forehead support that creates addition contact points betweenthe mask and the user's head. The forehead support minimizes themovement of the mask as well as minimizes uncomfortable pressure pointsof the mask by preventing the mask from pushing too strongly against theuser's nose and/or facial region.

[0008] Forehead supports typically have attached thereto a softcomfortable patient-contacting forehead pad. Forehead pads are generallyconstructed from soft materials, such as silicone, in contrast to theforehead support, which is generally rigid. One form of prior artforehead pad is disclosed in U.S. Pat. No. 6,119,693, the contents ofwhich are hereby incorporated by reference in their entirety.

[0009] A problem with existing forehead pads is the mechanism by whichthe pad is connected to forehead support. The pad must be secured insuch a way so as to be easy to insert and remove, but not beunintentionally dislodged. Furthermore, regardless of the relativeproximity between the forehead support/pad and the mask frame, thereshould be no sharp edges against which the user's face can make contact,leading to further discomfort.

[0010] One form of known forehead pad is used on the AIR PILOT mask,manufactured by MPV, Truma, Germany, shown in FIGS. 50 to 57. Thisforehead pad includes a stalk adapted to be pulled through a hole on anarm of a forehead support. The pad also includes two rows of three slotsadapted to engage with two rows of three teeth which project rearwardlyfrom the arm of the forehead support. Problems with this type offorehead pad include: (i) it is difficult to assemble; (ii) it isdifficult to remove; (iii) it may become dislodged during the night andpresent sharp teeth to the forehead of a patient; (iv) it has a vagueassembly which makes it difficult to know when it is in the correctposition; (v) its construction leads to regions of high pressure underthe teeth; and (vi) it presents an edge to the forehead of a patientwhen rocked at an angle.

[0011] A further problem with existing forehead pads is that they canlead to uneven pressure on the user's forehead, leading to discomfortand marks on the face. For example, one form of known forehead padincludes a patient contacting surface and a pair of reinforcing struts,as shown in FIGS. 16 to 17. During use, the pad is subject to acompressing force that can lead to pressure points, lines or ridges onthe patient contacting surface in the region where the reinforcingstruts join it. This can lead to uneven pressure on the user's forehead.The use of existing forehead pads also results in sweating by the user.

[0012] Another problem with a known form of forehead support is themechanism for engaging the forehead pad with the forehead support. Theforehead support includes a pair of rigid L-shaped catches c adapted toslidably engage with a recess in the forehead pad, as shown in FIGS. 18to 20. A problem can arise if a pad is not in position when the foreheadsupport is in use: the catch may abut against the forehead of a user.This can lead to discomfort and marking of the forehead.

[0013] Therefore, there exists a need in the art for a forehead pad thatovercomes the problems listed above.

SUMMARY OF THE INVENTION

[0014] One aspect of the invention is directed towards a mask assemblyhaving a forehead support and a forehead pad that provide more comfortto a user.

[0015] Another aspect of the invention is directed towards a foreheadpad that distributes contact pressure around the user's forehead.

[0016] Another aspect of the invention is directed towards a foreheadpad that permits a wide range of motion.

[0017] Another aspect of the invention is directed towards a foreheadpad that lessens or avoids contact between the user and the edges of theforehead pad.

[0018] Another aspect of the invention is directed towards a foreheadpad that achieves an even pressure distribution with no localizedregions of high forces.

[0019] Another aspect of the invention is directed towards providing aforehead pad that is easy to insert in a forehead support and isflexible enough to accommodate a range of different forehead sizes andshapes.

[0020] Another aspect of the invention is directed towards a foreheadpad that tapers smoothly from the support post to the base region,causing lines of force to be smoothly and evenly carried from thesupport post to the base region, resulting in an even distribution ofthe pressure across a user's forehead.

[0021] Another aspect of the invention is directed towards a foreheadpad for a forehead support of a respiratory mask that comprises a plateregion connected to a support post, the support post including aforehead support engaging mechanism.

[0022] Another aspect of the invention is directed towards a foreheadpad that it is relatively easy to engage with a forehead support butrelatively more difficult to disengage.

[0023] Another aspect of the invention is directed towards a foreheadpad that lessens or avoids contact between the user and the edges of theforehead support.

[0024] Another aspect of the invention is directed towards a foreheadpad that includes a base portion to contact a user's forehead, a supportpost comprising a necked down region connected to the base portion, anda head adapted to connect the support post to a forehead support of arespiratory mask.

[0025] Another aspect of the invention is directed towards a foreheadpad assembly that includes at least two pads, each pad comprising a baseportion to contact a user's forehead, a support post comprising a neckeddown region connected to the base portion, and a head adapted to connectthe support post to a forehead support of a respiratory mask. Theassembly further comprises at least one connector to connect adjacentbase portions.

[0026] Other aspects, features and advantages of this invention willbecome apparent from the following detailed description when taken inconjunction with the accompanying drawings, which are a part of thisdisclosure and which illustrate, by way of example, principles ofpreferred embodiments.

BRIEF DESCRIPTION OF FIGURES

[0027]FIG. 1 is a perspective view of a respiratory mask and foreheadpad according to one embodiment of the present invention;

[0028]FIG. 2 is a perspective and enlarged view of the forehead supportshown in FIG. 1, without the mask frame and pads;

[0029]FIG. 3 is a perspective view of one embodiment of a forehead padaccording to the present invention;

[0030]FIG. 4 is a perspective view of a respiratory mask and foreheadpad according to one second embodiment of the present invention;

[0031]FIG. 5 is a perspective view of another embodiment of a foreheadpad according to the present invention;

[0032]FIG. 6 is a top view of a forehead support including a pair offorehead pads and a forehead of a user;

[0033]FIG. 7 is a perspective view of the contact surface of oneembodiment of a forehead pad showing raised surfaces;

[0034]FIG. 8 is a cross-sectional view of one embodiment of a foreheadpad showing a hollowed out region;

[0035]FIG. 9 is a top view of an embodiment of a forehead pad assemblyshowing two pads joined by a flexible connector;

[0036]FIG. 10 is a right side view of one embodiment of a forehead padin a respiratory mask showing contact with a user;

[0037]FIG. 11 is a cross-sectional view of one embodiment of a foreheadpad engaged with one embodiment of a forehead support;

[0038]FIG. 12 is a cross-sectional view of another embodiment of aforehead pad engaged with another embodiment of a forehead support;

[0039]FIG. 13 is a cross-sectional view of another embodiment of aforehead pad engaged with another embodiment of a forehead support;

[0040]FIG. 14 is a cross-sectional view of another embodiment of aforehead pad engaged with another embodiment of a forehead support;

[0041]FIG. 15 is a top view of the embodiment of the forehead supportshown in FIG. 14;

[0042]FIG. 16 is a cross-section of a prior art forehead pad;

[0043]FIG. 17 is a cross-section of the forehead pad shown in FIG. 16 ina compressed state;

[0044]FIG. 18 is a cross-section of a prior art forehead pad;

[0045]FIG. 19 is a front view of a prior art forehead support;

[0046]FIG. 20 is a top view of the forehead support shown in FIG. 19;

[0047]FIG. 21 is a side view of another embodiment of a forehead padaccording to the present invention;

[0048]FIG. 22 is a bottom view of the embodiment shown in FIG. 21;

[0049]FIG. 23 is a top view of the embodiment shown in FIG. 21;

[0050]FIG. 24 is another side view of the embodiment shown in FIG. 21;

[0051]FIG. 25 is a cross-sectional view of the embodiment shown in FIG.24 along axis 25-25;

[0052]FIG. 26 is a perspective view of the embodiment shown in FIG. 21;

[0053]FIG. 27 is a perspective view of another embodiment of a foreheadsupport according to the present invention;

[0054]FIG. 28 is an end view of another embodiment of a forehead padaccording to the present invention;

[0055]FIG. 29 is a side view of the embodiment shown in FIG. 28;

[0056]FIG. 30 is a perspective view of the embodiment shown in FIG. 28;

[0057]FIG. 31 is a top view of the embodiment shown in FIG. 28;

[0058]FIG. 32 is a rear view of the embodiment shown in FIG. 9;

[0059]FIG. 33 is a top view of the embodiment shown in FIG. 32;

[0060]FIG. 34 is a front view of the embodiment shown in FIG. 32;

[0061]FIG. 35 is an end view of the embodiment shown in FIG. 9;

[0062]FIG. 36 is a cross-sectional view of the embodiment shown in FIG.35 along axis 36-36;

[0063]FIG. 37 is a an expanded cross-sectional view of the embodimentshown in FIG. 35;

[0064]FIG. 38 is a rear view of another embodiment a forehead padaccording to the present invention;

[0065]FIG. 39 is a top view of the embodiment shown in FIG. 38;

[0066]FIG. 40 is a cross-sectional view of the embodiment shown in FIG.38 along axis 40-40;

[0067]FIG. 41 is a front view of the embodiment shown in FIG. 38;

[0068]FIG. 42 is an end view of the embodiment shown in FIG. 39;

[0069]FIG. 43 is a cross-sectional view of the embodiment shown in FIG.42 along axis 43-43;

[0070]FIG. 44 is an expanded cross-sectional view of the embodimentshown in FIG. 42;

[0071]FIG. 45 is a cross-sectional view of one embodiment of a foreheadpad engaged with one embodiment of a forehead support according to thepresent invention;

[0072]FIG. 46 is side view of the embodiment shown in FIG. 45;

[0073]FIG. 47 is a cross-sectional view of another embodiment of aforehead pad engaged with another embodiment of a forehead supportaccording to the present invention;

[0074]FIG. 48 is a top view of the embodiment of the forehead pad andthe embodiment of the forehead support shown in FIG. 47;

[0075]FIG. 49 is a top view of the embodiment of the forehead padengaged with the embodiment of the forehead support shown in FIG. 47during an intermediate assembly step;

[0076]FIG. 50 is a front view of a prior art forehead pad;

[0077]FIG. 51 is a top view of the forehead pad shown in FIG. 50;

[0078]FIG. 52 is bottom side view of the forehead pad shown in FIG. 50;

[0079]FIG. 53 is a left view of the forehead pad shown in FIG. 50;

[0080]FIG. 54 is a top view of a prior art forehead pad;

[0081]FIG. 55 is a perspective view of the forehead pad shown in FIG.55;

[0082]FIG. 56 is a top view of a prior art forehead support;

[0083]FIG. 57 is a front view of a prior art forehead support;

[0084]FIG. 58 is a top view of another embodiment of a forehead padaccording to the present invention;

[0085]FIG. 59 is a front perspective view of another embodiment of aforehead pad according to the present invention;

[0086]FIG. 60 is a rear perspective view of the forehead pad shown inFIG. 59;

[0087]FIG. 61 is a cross-sectional view of the forehead pad shown inFIG. 59 along the minor axis;

[0088]FIG. 62 is a cross-sectional view of the forehead pad shown inFIG. 59 along the major axis;

[0089]FIG. 63 is a perspective view of another embodiment of a foreheadpad according to the present invention;

[0090]FIG. 64 is a cross-sectional view of another embodiment of aforehead pad according to the present invention;

[0091]FIG. 65 is a cross-sectional view of another embodiment of aforehead pad according to the present invention;

[0092]FIG. 66 is a cross-sectional view of another embodiment of aforehead pad according to the present invention;

[0093]FIG. 67 is a partial cross-sectional view another embodiment of aforehead pad according to the present invention;

[0094]FIG. 68 shows an embodiment of a forehead pad according to thepresent invention flexed in a first direction;

[0095]FIG. 69 shows an embodiment of a forehead pad according to thepresent invention flexed in a second direction;

[0096]FIG. 70 shows an embodiment of a forehead pad according to thepresent invention flexed in a third direction; and

[0097]FIG. 71 shows an embodiment of a forehead pad according to thepresent invention flexed in a fourth direction.

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS

[0098]FIG. 1 shows an example of a respiratory mask assembly 100. Themask assembly includes a frame portion 101, a forehead support 102, anda forehead pad 300. The mask is adapted to fasten securely andcomfortably to a user's face. In particular, the mask assembly 100comprises a seal-forming region 103 that covers the user's nose and/ormouth and a contains opening 104 to which an air delivery tube can beattached. Air or oxygen flows through the opening 104 under positivepressure.

[0099] The forehead support 102 is advantageously connected to the frameportion 101 of the mask assembly 100, e.g., by a pivot device 105, whichcan be adjusted to allow the forehead support 102 to the accommodate theconfiguration of a user's face. The forehead support 102 is preferablymade from a thermoplastic material. One embodiment of a forehead supportis shown in greater detail in FIG. 2.

[0100] The forehead support 102 can be configured to be essentiallystraight or it can be curved. The essential straight embodiment is shownin FIG. 2. In the case where the forehead support is curved, thecurvature generally follows the curvature of the user's forehead. Whilethis is the most likely structure, it is within the scope of the presentinvention to use a forehead support 102 that has the opposite curvature,or any combination thereof.

[0101] The forehead support 102 can be provided with one or moreopenings. These openings can be adapted to serve numerous purposesincluding points of connection to the mask frame, points of connectionto any another support surface, points of connection 201 for straps tosecure the mask to the user, and apertures 202 for a forehead pad.

[0102] In a preferred embodiment of the forehead support 102, theapertures 202 are designed to receive a head of the forehead pad 300.The apertures 202 can be disposed about the forehead support 102 in amanner to allow a user to adjust the position of the forehead pad 300.The apertures 202 are also designed to allow a user to attach theforehead pad 300 securely to the forehead support 102. In a preferredembodiment, the apertures 202 designed to allow a user to attach theforehead pad 300 securely and reversibly to the forehead support 102.

[0103] The forehead pad 300 in accordance with a first embodiment of theinvention is shown in greater detail in FIG. 3. The forehead pad 300comprises a base portion 305 to contact a user's forehead, a supportpost 301 connected to the base portion, and a head 302 adapted to beconnected to the forehead support 102. In this embodiment, the head 302is bullet or cone shaped, or otherwise tapered. However, other shapesare possible as long as they serve the purpose of the invention.

[0104] The base portion 305, support post 301, and head 302 can beseparate pieces, designed to fit with each other. In one embodiment, thebase portion 305 and the support post 301 can be constructed as onepiece. In another embodiment, the support post 301 and the head 302 canbe constructed as one piece. In yet another embodiment, the base portion305 and the head 302 can be constructed without a support post 301.Finally, in a preferred embodiment, the base portion 305, the supportpost 301, and the head 302 are molded integrally into one piece.

[0105] The embodiment shown in FIG. 3 contains a necked down region 303between the base of the head 302 and the top of the support post 301. Ina preferred configuration, the forehead pad is adapted to releasablyengage with the forehead support 102. The function of the necked downregion 303 is to facilitate this feature. The necked down region 303 issuch that its diameter is smaller than the diameter of the base of thehead 302. This results in a lip 310 between the base of the head 302 andthe necked down region 303 and another lip 311 between the necked downregion 303 and the support post 301.

[0106] In a preferred embodiment, the necked down region 303 is at leastas long as the length of the aperture 202 (FIG. 2) in the foreheadsupport 102. Insertion of the pad 300 through a first end 200 of theaperture in the forehead support 102 results in the head 302 passingthrough the aperture 202 and emerging out a second end 210. The supportpost 301 remains on the side of the first end 200 of the aperture 202with the necked down region 303 occupying at least the length of theaperture. This feature results in easy insertion and a tight fit.

[0107] Typically, this insertion can be carried out by a user byapplying axial pressure to the base portion 305 of the pad 300. Whilethe support post 301 is flexible, it can withstand the forces needed forassembly. Using the forehead pad embodiment described in FIG. 3 and theforehead support described in FIG. 2 as examples, the head 302, as wellas the lip 310 distort as axial force is applied against the first end200 of the aperture 202, until the head 302 and the lip 310 reach asecond end 210 of the aperture 202, whereupon the lip 310 re-expands toengage a first surface 215 of the forehead support 102 adjacent to theaperture 202. Further, the lip 311 abuts against a second surface 205 ofthe forehead support 102, to prevent axial movement of the pad 300.

[0108] The removal of the pad occurs by applying a pulling force it in adirection opposite to the axial force applied for insertion. Once again,the head 302 and the lip 310 distort as the lip 310 disengages with thefirst surface 215 of the forehead support 102 adjacent to the aperture202. Lip 311 disengages with the second surface 205 of the foreheadsupport 102. Both the head 302 and the lip 310 regain their originalshape after disengagement from the forehead support 200.

[0109] The pressure can be applied by a user's fingers and thesuccessful insertion of the pad 300 is indicated not only by theemergence of the head 302 through the first surface 215 of the aperture202 but typically also by a clicking sound. The combination of sight,sound, and ease of insertion is useful for aged or otherwise infirmusers with limited manual and/or digital dexterity. The sound producedhas the added benefit of providing the user of knowledge that the pad300 has been successfully inserted in the dark. This feature can be ofimportance due to the fact that the masks are used at night. Both theforehead support 102 and the forehead pad 300 are configured such thatthe pad 300 can be placed in different positions on the support 102 soas to achieve different positions of contact on the user's forehead.

[0110] A wide variety of methods well known to a person skilled in theart for the manufacture of the base portion, support post, and head. Apreferred method of manufacture is by injection molding.

[0111] The support post 301 can project from the base portion 305 at anangle α, defined between a tangent t to the outer surface of the baseportion 305 at a point of contact between the support post 301 and thebase portion 305. This angle α can be about 90°, i.e., the support post301 extends essentially straight out from the base portion 305. FIG. 3shows an embodiment of a forehead pad 300 in which the angle α is about90°.

[0112]FIG. 4 shows another embodiment of a respiratory mask assembly410. The mask assembly 410 includes of a frame portion 411, a foreheadsupport 412, and another embodiment of a forehead pad 400. The foreheadsupport 412 is advantageously connected to the frame portion 411 of themask 410, e.g., by a pivot device 413. The mask assembly 410 comprises aseal-forming cushion 414 that covers a user's nose and/or mouth andcontains a swivel elbow 415. The swivel elbow 415 is adapted to receivea supply of air or oxygen flows at positive pressure.

[0113]FIG. 5 shows another embodiment of a forehead pad 400 in greaterdetail. This embodiment of the pad 400 includes a base portion 408, asupport post 401, and a head 402. The general construction and operationis similar to that of the first embodiment although there are severaldifferences in the construction, for example, the angle β between thetangent t to the outer surface of the base portion 406 at a point ofcontact between the support post 401 and the base portion 408 is betweenabout 60° and about 120°. Preferably, the angle β is about 70°. Oneadvantage of a support post 401 projecting at an angle less than 90° isto allow the base portion 400 to better fit the contours of a user'sforehead, as shown in FIG. 6.

[0114] The support post 401 can be constructed in a manner so as to makeit more flexible. For example, the support post 401 includes cut awayportions 405. These cut away portions help the support post to be ableto be bent or flexed, varying the angle β in use. In this way, a supportpost 401 of larger diameter may be used while still retaining a degreeof flexibility as shown in FIGS. 68 to 71.

[0115] The base portion 408 can be of any shape, preferably in apad-like configuration. In one embodiment, a contact region 407 of thebase portion 408 is shaped so that the transmission of contact forces tothe surface of the forehead of the user takes place underphysiologically compatible pressures, as shown in FIG. 58. In apreferred embodiment, the contact region 407 is concavely curved tofollow the curvature of a forehead.

[0116] The contact region 407 can optionally include a raised surfacepattern 510 as shown in FIG. 7. The pattern 510 reduces the possibilityof a suction effect of the pad 400 thereby reducing the drawing of bloodin the region and making the pad 400 more comfortable. The raisedpattern 510 has the added benefit of reducing sweating. In anotherembodiment, a rear surface of the pad 406 is given a sand-blasted finishto improve ventilation and reduce the likelihood of sweating.

[0117] The base portion 408 and support post 401 of the pad 400 can alsoinclude a hollowed out region 608 extending a pre-determined distance601 into the base portion 408 and/or the support post 401 as shown inthe cross-sectional view in FIG. 8. In the embodiment shown, thehollowed out region 608 extends through the base portion 408 and partlyinto the support post 401. This structure imparts a degree ofspringiness and flexibility to the forehead pad 400. Due to theessentially incompressible nature of silicone, some cut away regions 405assist flexibility. The use of the hollowed out region 608 allows forsome movement along an axis through the support post 401.

[0118] Increasing the diameter of the support post 401 makes theforehead pad 400 easier to insert into the forehead support 102.Furthermore, a larger diameter reduces the likelihood of localizedpressure points. However, as the support post 401 is made thicker, itbecomes less flexible. Hence the preferred embodiment of the inventionbalances ease of insertion with flexibility.

[0119] In another embodiment, the hollowed out region 608 extendsthrough the base portion 408, the support post 401, and the head 402resulting in a through-bore 509 (shown in FIG. 7). The through-bore 509may further facilitate compression of the support post 401 and head 402during assembly and disassembly. This structure allows a flow of airand/or moisture to occur from the user's skin to the atmosphere,resulting in a reduction of sweating and a more comfortable pad 400.

[0120] The support post 401 has a diameter that is in its broadestaspect between about 0.1 cm and about 3.0 cm. More specifically thediameter of the support post of the embodiment of FIG. 9 is betweenabout 0.5 cm and about 1.25 cm, and most preferably the diameter isabout 1 cm. The term “about” is meant to indicate that the diameters arenot absolute and can be deviated by one skilled in the art. Alternativeembodiments, such as those shown in FIGS. 21 to 31 have differentdiameters.

[0121] The support post 401 has a length that is in its broadest aspectbetween about 0.1 cm and about 2.5 cm. More specifically the length isbetween about 0.5 cm and about 1.25 cm, and most preferably the lengthis about 1 cm. Dimensions for one form of forehead pad are shown in FIG.37. Once again, the term “about” is meant to indicate that the lengthsare not absolute and can be deviated by one skilled in the art.

[0122] The support post 401 can be straight or it can taper. An exampleof a straight support post is shown in the embodiment in FIG. 3. Thetaper can also be such that the region at the base portion is thickerthan the head region, as shown in the embodiment in FIG. 5.

[0123] As would be understood by one skilled in the art, a wide varietyof materials can be used to manufacture the forehead pad in accordancewith the present invention. Features of any material used should includebiocompatibility, flexibility and comfort. Some examples of suchmaterials include rubber and flexible plastics. In a preferredembodiment, the pad is constructed from cured Liquid Silicone Rubber(Part# 2666031, Silastic 94-595-HC) manufactured by Dow Coming,alternatively a silicone with a hardness of approximately 35-45 Shore Amay be used. These examples are merely intended to be illustrative andare not limiting in any manner.

[0124] In accordance with a preferred embodiment of the presentinvention, at least two base pads can be joined in a forehead padassembly 700. In this embodiment, two versions of which are shown inFIGS. 9 and 32 to 44, a connector 711 is used to connect adjacent baseportions 708. Any type of connector can be used such as a strap or aflexible bridge portion. An advantage of a connector is that theassembly 700 has a one-piece design which is less likely to be lost. Theplurality of base portions 708, with contact regions 707, and connectors711 can be integrally formed with each other.

[0125] As mentioned earlier, the hollowed out region 608 can extend apre-determined distance into the base portion 708 and/or the supportpost 701. This distance can be adjusted to increase flexibility of theforehead pad assembly 700. For example, the hollowed out region 608extends a longer distance into the support post 701 in the embodimentshown in FIG. 44 when compared to the embodiment shown in FIG. 37.Increasing the distance of the hollowed out region 608 has severaladvantages including flexibility, minimization of contact with the edgesof the base portion 708, and better airflow resulting in a reduction insweating by the user.

[0126] The hollowed out region 608 can also have a variety of shapesincluding conical, pyramidal, cylindrical, or combinations thereof. Itis within the scope of this invention that the hollowed out region 408have additional sub-structures within it including ridges, bumps, orholes.

[0127] In a preferred embodiment, the two base portions 708 of aforehead pad assembly 700 are adapted in order to be situated above leftand right eyebrows of the user. As shown in FIG. 10, a base portion 708is shown against the user's forehead 813. The support post 701 isdesigned to act as a spring along the direction of arrow 814. The cutaway portions 705 improve its flexibility while maintaining ease ofinsertion. Another advantage of this design is that it can betteraccommodate rolling and twisting of the mask 410. A further advantage ofthe support post 701 is that its diameter is optimized to reduce theeffect of a single point of pressure on the forehead 813.

[0128] The cut away portions 705 define an undercut 720 between the cutaway portions 705 and the base portion 708. The undercut 720 can be avariety of shapes including curved, square, conical, triangular, or anycombinations thereof. The undercut 720 depth e can also be varied. Thedepth e can range between about 0.25 mm to about 1.25 mm, preferablybetween about 0.5 mm and about 1 mm, and most preferably about 0.75 mm.The term “about” is meant to indicate that the widths and lengths arenot absolute and can be deviated by one skilled in the art.

[0129] The number, shape, and size, width w, and length l of the cutaway portions 705 can be varied to serve a variety of purposes includingease of insertion, ease of removal, flexibility of motion whenunassembled with the forehead support, flexibility of motion whenassembled with the forehead support, minimization of contact between theuser and the edges of the base portion 708, minimization of contactbetween the user and the edges of the forehead support 102, and anglesbetween the forehead pad assembly 700 and the forehead support 102. Thewidth w can range between about 0.25 mm to about 1.25 mm, preferablybetween about 0.5 mm and about 1 mm, and most preferably about 0.75 mm.The length l can range between about 0.05 mm to about 1.5 mm, preferablybetween about 0.25 mm and about 1 mm. Once again, the term “about” ismeant to indicate that the widths and lengths are not absolute and canbe deviated by one skilled in the art.

[0130] The cut away portions 705 can have regions of similar ordifferent widths w and similar or different lengths l. Comparison of theembodiment of the forehead pad assembly 700 shown in FIGS. 32 to 37 withthe embodiment of the forehead pad assembly 700 shown in FIGS. 38 to 44shows a few variations in the cut away portions 705. The width w of thecut away portions 705 in the embodiment shown in FIGS. 38 to 44 is lessthan the width w of the cut away portions 705 in the embodiment shown inFIGS. 32 to 37.

[0131] The undercut 720 in FIG. 40 (a cross-sectional view along line40-40 of FIG. 39) may be more pronounced than the embodiment of FIGS. 32to 37. Thus the range of movement of the pad in the vertical plane canbe increased, thereby increasing the range of users the mask will fit.In addition, the increased range of movement can help prevent the edgeof the pad from coming in contact with the user's forehead, therebyincreasing user compliance and comfort. Finally, the increased undercut720, along with the shape and size of the surrounding cut away portions705, can effect the force necessary to flex the base portion 708 withrespect to the support post 701, thereby optimizing the desired flexingforces within levels acceptable to the user while still allowingadequate performance of the forehead pad assembly 700.

[0132] One advantage of reducing the width w and/or increasing the depthC is to vary the angle δ between the forehead pad assembly 700 and theforehead support 102, which in turn allows for greater range of motionand user comfort. The angle δ is the angle between a horizontal line hand a line passing through the center of the base portion 708 and thesupport post 701. FIGS. 45 and 46 show the embodiment of the foreheadpad assembly 700 shown in FIGS. 38 to 44 assembled with the foreheadsupport 102. The angle δ is about 25°. The angle δ of the embodiment ofthe forehead pad assembly 700 shown in FIGS. 32 to 37 assembled with theforehead support 102 is about 0°. Once again, the term “about” is meantto indicate that the angles are not absolute and can be deviated by oneskilled in the art.

[0133] Presentation of the base portion 708 of the forehead pad assembly700 at an angle which is generally parallel to the users foreheadprovides improved comfort to the user, reducing the likelihood ofpressure sores which may result from an uneven presentation. In someforms of long masks, for example a full face mask, the forehead support102 may be positioned in use higher up the forehead of the user than ina nasal mask.

[0134] In the embodiment of forehead support shown in FIG. 42, thesupport post 701 and base portion 708 are generally perpendicular to oneanother when viewed from an end. However, in other embodiments, they maybe constructed at different angles. For a long mask, because of thecurvature of the skull, in order that the base portion 708 of theforehead pad assembly 700 be presented generally parallel to the user'sforehead, either (i) the forehead support 102 should be adapted toretain a perpendicular forehead pad assembly 700 at an angle, as shownin FIG. 45, or (ii) the forehead support 102 should be adapted to retaina non-perpendicular forehead pad assembly 700 at a right angle. In thepreferred embodiment, a perpendicular pad is used and the foreheadsupport 102 is adapted to retain and present the pad to the forehead ofthe user at the appropriate angle. In this way, the same forehead padassembly 700 can be used across a range of mask systems, for example,nasal masks and full face masks, providing an economic benefit to themanufacturer through the use of common parts.

[0135]FIG. 11 shows a cross section of an embodiment of a forehead pad900 inserted into an aperture 930 in a forehead support 940. To insertthe pad 900, axial force is applied in the direction of arrow 914. Thehead 902 and the lip 904 distort as they pass through the aperture 930.Once the head 902 and the lip 904 are through the aperture 930, thenecked down region 903 of the support post 901 occupies the length ofthe aperture 930. This results in the lip 905 also making contact withthe forehead support 940. The engagement of lips 904 and 905 withrespective side surfaces of the forehead support 940 results inmaintaining the pad 900 in position.

[0136] To remove the pad 900 from the forehead support 940 the pad 900is pulled in an opposite direction to arrow 914. Once again, the head902 and/or the lip 904 distort as they pass through the aperture 930enable the pad 900 to disengage from the forehead support 940.

[0137]FIG. 12 shows a cross section of an embodiment of a forehead pad408 inserted into another embodiment of a forehead support 1040. Theforehead support 1040 has arms 2000 that can move in direction d whenpressure is applied to the pad 408 in direction a. In one embodiment,the movement of arms 2000 results in a plastic deformation, i.e., theremoval of the pad 408 results in the arms 2000 remaining essentially inthe position they were when the pad 408 was inserted. In anotherembodiment, the movement of arms 2000 results in an elastic deformation,i.e., the removal of the pad 408 results in the arms 2000 returningessentially to the position they were before the pad 408 was inserted.The support post 401 can compress in direction b allowing for ease ininsertion and removal but still providing a firm fit. Once inserted, thepad 408 can be adjusted by angle γ.

[0138] A cross section of another embodiment of a forehead pad 1000engaged with a rigid forehead support 1040 is shown in FIG. 13. Theforehead support 1040 comprises lips 1042 and 1043. Lip 1042 of theforehead support 1040 is adapted to engage lip 1004 of the head 1002 andlip 1043 of the support post 1040 is adapted to engage lip 1005 of thesupport post 1010. In another embodiment of the invention, the supportpost 1010 is co-molded to the forehead support 1040.

[0139]FIGS. 14 and 15 shown another embodiment of a forehead pad 100engaged with an embodiment of a forehead support 1040. The foreheadsupport 1040 has arms 2001. These arms 2001 define the aperture 1030 andcan be moved in direction a to allow for removal of the pad 1000.

[0140] In another embodiment of the invention, the support post 1010includes a generally cylindrical end region adapted to engage with akey-shaped slot of a forehead support. To attach the stalk to theforehead support, a small-diameter portion of the end region is slidthrough a generally rectangular region of smaller diameter, causing itto distort, before being received within a generally cylindrical regionhaving a diameter slightly larger than that of the stalk, as in FIGS. 47to 49. The smaller diameter portion of the end region defines twoshoulder regions, similar in function to those of other embodiments,adapted to prevent axial movement of the pad.

[0141] In one form, the base portion 408 of the forehead pad isgenerally plate- or disc-shaped. In a preferred form, it presents aconcave surface to a forehead of a patient in use. Possible shapes ofthe base portion include rectangular and oval shapes.

[0142] The shape of the support post 401 and base region 408 is designedto cause lines of force 490 to be smoothly and evenly carried from thesupport post 401 to the base region 408, as shown in FIG. 58. In thisway there is an even distribution of pressure across the user's forehead813. The lines of force 490 are not concentrated. The support post 410is of a design to be sufficiently rigid so that it does not buckle wheninserted and pushed.

[0143] An alternative embodiment of a forehead pad according to thepresent invention is shown in FIGS. 59 to 62. In this embodiment, thereis a “cleat” on the T-bar arm of the forehead support, the cleat havinga generally oval shape and positioned away from the surface of the armof the forehead support, defining a space between the front side of thecleat and the arm of the forehead support. The pad has a generally ovalshape, defining a major and minor axis and includes a shaft therethroughwith a varying profile. The initial profile is of a complementary shapeto the cleat, allowing the pad to fit on the cleat. Further along theshaft, the profile rotates approximately 90°, defining a shoulderregion. In this way, the pad can be inserted over the cleat and thentwisted approximately 90° to lock it in position. In this position, theshoulder region of the pad engages with the front side of the cleat.

[0144] In a preferred embodiment, the pad includes a pair of dimplesadapted to engage with corresponding protrusions on the arm of theforehead support. Engagement between the dimples and respectiveprotrusions provides feedback to the user that the pad has beencorrectly rotationally aligned. Furthermore, the engagement betweendimples and protrusions reduces unintentional rotational movement of thepads. Alternative locking mechanisms, such as those with keys ormoveable slider blocks, fall within the scope of the invention.

[0145]FIG. 63 shows an alternative embodiment of the invention. In thisembodiment, the arms of the forehead support 102 are generallycylindrical and are covered in a generally cylindrical “pipe” of foam,forming the forehead pad 400. Because of the generally constant radiusof the forehead arm and the pipe, there are no sharp edges presented tothe forehead of the user, regardless of the angle of the support withrespect to the forehead. In one form, the foam only partly surrounds thearm of the forehead support. Furthermore, because of the generallyconstant properties of the foam with respect to angular position, thelines of force are smoothly carried to the forehead of the user. Inanother embodiment, the pipe is shaped so that its outer surfacepositions a thicker section at the forehead and the bore through thepipe need not be circular, permitting attachment to non-circular arms.

[0146] In alternative embodiments, shown in FIGS. 64 to 66, thethickness of the pipe about a circumference can be varied to provideadjustability. The pipe can have two sections of different thicknesses(FIG. 64), three sections of different thickness (FIG. 65), or can havean eccentric thickness (FIG. 66). These embodiments offer several otheradvantages including increasing the snugness of the fit without removalof the mask, decreasing tightness of the pipe and associated symptoms,e.g., sweating and discomfort, without removal of the mask.

[0147]FIG. 67 shows an alternative embodiment of the invention. In thisembodiment, the tip of the forehead support 102 comprises a generallyspherical ball. A foam or silicone pad 400, also generally sphericallyshaped, is placed over the tip of the forehead support 102. The generalspherical shape smoothly carries lines of force from the tip of theforehead support to the forehead, regardless of orientation. In this waythere is an even distribution of force on the forehead of the user.

[0148] While this application has described a few embodiments offorehead pads and forehead supports, it is well understood by oneskilled in the art that various forehead pads, forehead supports, andmasks can be used interchangeably. A type of forehead pad is not limitedto a particular forehead support or to a specific mask.

[0149] In an alternative embodiment, the support post of the foreheadpad can be used in combination with an extruded pad such as used on theMIRAGE mask (U.S. Pat. No. 6,119,693). Another embodiment has a foreheadpad devoid of a convex surface, instead including a support post used incombination with a concave surface. Another embodiment includes a padwith varying cross-sectional thicknesses, e.g., it could be thinner atedges for greater flexibility when rolling, than at the center..

[0150] It can thus be appreciated that the aspects of the presentinvention have been fully and effectively accomplished. The foregoingspecific embodiments have been provided to illustrate structural andfunctional principles of the present invention, and are not intended tobe limiting. To the contrary, the present invention is intended toencompass all modifications, alterations and substitutions within thespirit and scope of the present invention.

What is claimed is:
 1. A forehead pad comprising: a) a base portion,wherein the base portion defines (i) a first surface, and (ii) a secondsurface to contact a user's forehead, wherein the second surface isconcave; b) a support post, wherein the support post projects from thefirst surface and comprises a necked down region; and c) a head adaptedto connect the support post to a forehead support of a respiratory mask.2. A forehead pad according to claim 1, wherein the support postprojects from the base portion and is integrally molded therewith.
 3. Aforehead pad according to claim 1, wherein the support post projectsfrom the first surface of the base portion at an angle, wherein theangle is defined between a tangent to the first surface at a point ofcontact between the support post and the base portion, and wherein theangle is between about 60° and about 120°.
 4. A forehead pad accordingto claim 3, wherein the angle is less than about 90°.
 5. A forehead padaccording to claim 4, wherein the angle is between about 65° and about80°.
 6. A forehead pad according to claim 1, wherein the second surfacedefines a raised surface pattern to at least one of: aid in airflow,prevent sweating, and increase comfort to the user.
 7. A forehead padaccording to claim 1, wherein the base portion and support post includea hollowed out region extending a pre-determined distance into at leastone of the base portion and support post.
 8. A forehead pad according toclaim 1, wherein the support post includes a tapered portion such that aregion at the base portion is thicker than the head.
 9. A forehead padaccording to claim 1, wherein the head includes a tapered portion fromthe support post to a point.
 10. A forehead pad according to claim 1,wherein the diameter of the necked down region is less than the diameterof a base of the head.
 11. A forehead pad according to claim 1, whereinthe support post is axially compressible.
 12. A forehead pad accordingto claim 11, wherein the support post includes at least one cut awayportion.
 13. A forehead pad according to claim 12, wherein the at leastone cut away portion has a length of between about 0.05 mm to about 1.5mm.
 14. A forehead pad according to claim 13, wherein the at least onecut away portion has a length of between about 0.25 mm and about 1 mm.15. A forehead pad according to claim 12, wherein the at least one cutaway portion has a width of between about 0.25 mm to about 1.25 mm. 16.A forehead pad according to claim 15, wherein the at least one cut awayportion has a width of between about 0.5 mm and about 1 mm.
 17. Aforehead pad according to claim 16, wherein the at least one cut awayportion has a width of between about 0.75 mm.
 18. A forehead padaccording to claim 12, wherein the support post further includes atleast one undercut.
 19. A forehead pad according to claim 18, whereinthe at least one undercut has a depth of between about 0.25 mm to about1.25 mm.
 20. A forehead pad according to claim 15, wherein the at leastone undercut has a depth of between about 0.5 mm and about 1 mm.
 21. Aforehead pad according to claim 16, wherein the at least one undercuthas a depth of between about 0.75 mm.
 22. A forehead pad according toclaim 1, wherein the support post has a diameter of between about 0.1 cmto about 1.5 cm.
 23. A forehead pad according to claim 22, wherein thesupport post has a diameter of between about 0.5 cm to about 1.25 cm.24. A forehead pad according to claim 23, wherein the support post has adiameter of approximately 1 cm.
 25. A forehead pad according to claim 1,wherein the support post has a length of between about 0.1 cm to about1.5 cm.
 26. A forehead pad according to claim 25, wherein the supportpost has a length of between about 0.5 cm to about 1.25 cm.
 27. Aforehead pad according to claim 26, wherein the support post has alength of approximately 1 cm.
 28. A forehead pad according to claim 1,wherein the head is adapted to be releasably connected to the foreheadsupport using a push-on motion.
 29. A forehead pad according to claim 1,wherein the support post is sufficiently rigid to distribute the linesof force from the forehead support evenly across the second surface ofthe forehead pad.
 30. A forehead pad according to claim 1, wherein thesupport post and the base portion are configured to evenly distributeforces across the second surface without localized pressure points. 31.A forehead pad according to claim 1, wherein the forehead pad consistsof the base portion, the support post, and the head.
 32. A forehead padaccording to claim 1, wherein the second surface consists essentially ofthe support post, which is substantially centrally mounted on the secondsurface.
 33. A forehead pad consisting essentially of: a) a base portionto contact a user's forehead; and b) a support post connected to acentral portion of the base portion.
 34. A forehead pad according toclaim 33, wherein the support post is substantially centrally mounted onthe base portion.
 35. A forehead pad comprising: a) a base portion tocontact a user's forehead; b) a support post connected to the baseportion; and c) a head adapted to connect the support post to a foreheadsupport of a respiratory mask, wherein the support post distributeslines of force from the head through the support post to the baseportion such that the lines of force are substantially evenlydistributed across the base portion.
 36. A respiratory mask comprising:a) a forehead support having an aperture and an otherwise entirelysmooth surface facing a user in use of the mask; and b) a forehead padcomprising a base portion, wherein the base portion defines a firstsurface and a second surface opposite the first surface to contact auser's forehead; a support post, wherein the support post projects fromthe first surface; and a head adapted to connect the support post to theforehead support.
 37. A forehead pad assembly comprising at least twoforehead pads, each pad comprising: a) a base portion to contact auser's forehead; b) a support post connected to the base portion,wherein the support post comprises a necked down region; and c) a headadapted to connect the support post to a forehead support of arespiratory mask; wherein the assembly further comprises at least oneconnector to connect adjacent base portions.
 38. A forehead padaccording to claim 37, wherein each base portion is adapted to bedisposed above an eyebrow of the user.
 39. A forehead pad according toclaim 37, wherein the connector is flexible.
 40. A forehead padaccording to claim 37, wherein at least two base portion and at leastone connector are integrally formed with each other.
 41. A forehead padaccording to claim 37, wherein at least one base portion and at leastone connector are formed as one piece.
 42. A forehead pad according toclaim 37, wherein the base portion defines a first surface, from whichthe support post projects.
 43. A forehead pad according to claim 42,wherein the support post projects from the first surface of the baseportion at an angle, wherein the angle is defined between a tangent tothe first surface at a point of contact between the support post and thebase portion, and wherein the angle is between about 60° and about 120°.44. A forehead pad according to claim 43, wherein the angle is less thanabout 90°.
 45. A forehead pad according to claim 44, wherein the angleis between about 65° and about 80°.
 46. A forehead pad according toclaim 42, wherein each base portion defines a second surface that isadapted to contact the user's forehead, and wherein the second surfaceis concave.
 47. A forehead pad according to claim 46, wherein the secondsurface defines a raised surface pattern to at least one of: aid inairflow, prevent sweating, and increase comfort to the user.
 48. Aforehead pad according to claim 37, wherein each base portion andsupport post include a hollowed out region extending a pre-determineddistance into at least one of the base portion and support post.
 49. Aforehead pad according to claim 37, wherein the support post includes atapered portion such that a region at the base portion is thicker thanthe head.
 50. A forehead pad according to claim 37, wherein the headincludes a tapered portion from the support post to a point.
 51. Aforehead pad according to claim 37, wherein the diameter of the neckeddown region is less than the diameter of a base of the head.
 52. Aforehead pad according to claim 37, wherein the support post is axiallycompressible.
 53. A forehead pad according to claim 52, wherein thesupport post includes cut away portions.
 54. A respiratory maskcomprising: a) a forehead support; and b) a forehead pad comprising: (i)a base portion, wherein the base portion further defines: a firstsurface, and a second surface to contact a user's forehead, wherein thesecond surface is concave; (ii) a support post, wherein the support postprojects from the first surface and comprises a necked down region; and(iii) a head adapted to connect the support post to a forehead support.55. A respiratory mask according to claim 54, wherein the foreheadsupport is essentially straight.
 56. A respiratory mask according toclaim 54, wherein the forehead support is curved.
 57. A respiratory maskaccording to claim 54, wherein the forehead pad connected to theforehead support does not project a hard surface to the user' forehead.58. A respiratory mask according to claim 54, wherein the forehead padis secured to the forehead support by only the support post.
 59. Arespiratory mask according to claim 54, wherein the support post isaxially compressible.
 60. A respiratory mask according to claim 59,wherein the support post includes cut away portions.
 61. A respiratorymask according to claim 54, wherein the forehead support includes atleast one aperture.
 62. A respiratory mask according to claim 61,wherein the forehead support comprises compressible regions in proximitywith the aperture.
 63. A respiratory mask according to claim 61, whereinthe head includes a tapered portion from the support post to a point inorder to releasably insert the head in the aperture.
 64. A respiratorymask according to claim 61, wherein the diameter of the necked downregion is less than the diameter of a base of the head, such that thehead can be releasably inserted into the aperture in order to securelyattach the forehead pad to the forehead support.
 65. A respiratory maskcomprising: a) a forehead support; and b) a forehead pad comprising: (i)a base portion, wherein the base portion further defines: a firstsurface, and a second surface to contact a user's forehead; (ii) asupport post, wherein the support post projects from the first surfaceand is adapted to connect to the forehead support, wherein the baseportion is connected to the forehead support solely through the supportpost.
 66. A respiratory mask according to claim 65, wherein a surface ofthe forehead support that faces the forehead pad includes noprotrusions.
 67. A forehead pad comprising: a) a base portion, whereinthe base portion further defines: (i) a first surface, and (ii) a secondsurface to contact a user's forehead; b) a support post, wherein thesupport post projects from the first surface and is adapted to connectto the forehead support, wherein the second surface substantially evenlydistributes force across the forehead pad without localized pressurepoints.